diff --git a/openbsc/tests/channel/Makefile.am b/openbsc/tests/channel/Makefile.am
index 5a3477c..6b7468c 100644
--- a/openbsc/tests/channel/Makefile.am
+++ b/openbsc/tests/channel/Makefile.am
@@ -10,6 +10,7 @@
 	$(top_srcdir)/src/timer.c \
 	$(top_srcdir)/src/select.c \
 	$(top_srcdir)/src/talloc.c \
-	$(top_srcdir)/src/gsm_data.c
+	$(top_srcdir)/src/gsm_data.c \
+	$(top_srcdir)/src/signal.c
 channel_test_LDADD = -ldl -ldbi